Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 423 [Rate centres in NPA 423] [Dial plan for NPA 423]

NXX: 666

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-666 A Elizabethton TN JHCYTNXCXPX  525E ONVOY, LLC - TN 956      
423-666 0 Elizabethton TN   525E ONVOY, LLC - TN 956   2019-07-10   
423-666 1 Elizabethton TN   525E ONVOY, LLC - TN 956   2019-07-10   
423-666 2 Elizabethton TN   073H TELNYX LLC 956   2021-01-23   
423-666 3 Elizabethton TN   525E ONVOY, LLC - TN 956   2023-02-10   
423-666 4 Elizabethton TN   624H ONVOY SPECTRUM, LLC 956   2023-04-27   
423-666 5 Elizabethton TN   525E ONVOY, LLC - TN 956   2021-07-10   
423-666 6 Elizabethton TN   525E ONVOY, LLC - TN 956   2018-06-16   
423-666 7 Elizabethton TN   525E ONVOY, LLC - TN 956   2019-06-23   
423-666 8 Elizabethton TN   525E ONVOY, LLC - TN 956   2018-06-16   
423-666 9 Elizabethton TN   525E ONVOY, LLC - TN 956   2019-07-10   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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